This invention relates to obtaining images of structures, such as tumors or lesions, in bodily tissue.
Modern imaging techniques have reduced the need for major surgical procedures to identify foreign structures in bodily tissue. For example, pressure sensors can be used to obtain a topographic image of bodily tissue and to determine the xe2x80x9chardnessxe2x80x9d (or density) of a structure in the tissue based on an amount of resistance provided by the structure. If the structure is relatively hard, it is more likely to be malignant, whereas if the structure is relatively soft, it is less likely to be malignant.
Ultrasound is another imaging technique that is used to obtain images of bodily tissue. Ultrasound provides narrow, cross-sectional slices of bodily tissue which make it possible, in some cases, to distinguish between benign and malignant tumors without major surgery. Readings from ultrasound devices are dependent upon the location and pressure applied to the ultrasound device.
For example, in breast cancer diagnoses, a technique known as xe2x80x9celastographyxe2x80x9d is implemented using ultrasound. According to this technique, while a structure is being examined, an ultrasound scanning head is pressed into the breast causing a compressive load on the structure and its surrounding tissue. By noting the relative change in the structure""s size as more load is applied, a user can make a qualitative assessment of how hard the structure is, with the assumption that a hard structure is more apt to be malignant. This same procedure can be repeated to determine if a structure has changed since a previous examination.
In general, in one aspect, the invention features obtaining image data for a structure through bodily tissue. An imaging sensor contacts the bodily tissue to obtain the image data for the structure. A pressure sensor is oriented in a substantially same direction as the imaging sensor. The pressure sensor contacts the bodily tissue to produce a signal that corresponds to an amount of pressure between the pressure sensor and the bodily tissue.
Among the advantages of this aspect of the invention may be one or more of the following. In order to determine if the consistency and/or size of a structure has changed between examinations, it is important to ensure that the pressure and orientation of sensors in a subsequent examination is similar to the pressure and orientation of sensors in a previous examination. The pressure sensor provides a way of doing this. For example, the pressure sensor can be used to measure an amount of pressure at a particular orientation of the imaging sensor. This pressure can then be duplicated during a subsequent examination, thereby providing more reliable examination results.
This aspect of the invention may include one or more of the following features. The imaging sensor is an ultrasound transducer. The pressure sensor is part of an array of pressure sensors and the imaging sensor is part of an array of imaging sensors. The array of pressure sensors is arranged at locations along an outer perimeter of the array of imaging sensors. Each pressure sensor produces a signal that is indicative of an amount of pressure between the pressure sensor and the bodily tissue. A processor analyzes signals from the pressure sensors to determine if an orientation of the pressure sensors is the same as a previous orientation of the pressure sensors.
A device may be included which provides an indication of the amount of pressure between the pressure sensor and the bodily tissue based on the pressure signal. The device comprises circuitry which receives the signal from the pressure sensor and the image data obtained by the imaging sensor, and which generates the indication and an image of the structure. The indication can comprise a visual indication and may be implemented using one or more light-emitting diodes which illuminate in accordance with the signal. Alternatively, the visual indication may be a computer monitor or other display device. The indication can comprise an audio indication, such as an audible tone that varies in accordance with the signal. This aspect of the invention may be incorporated into one of, e.g., an ultrasonic endoscope, a laparoscope, a transesophogeal ultrasonic endoscope, an intravascular catheter, an ultrasonic gastric endoscope, a duodenoscope, and a colonoscope.
In general, in another aspect, the invention features obtaining image data for a structure through bodily tissue. An imaging sensor contacts the bodily tissue to obtain image data for a first image of the structure. A pressure sensor is oriented in a substantially same direction as the imaging sensor, which contacts the bodily tissue to obtain data for a second image of the structure. The second image is a different perspective of the structure than the first image.
Among the advantages of this aspect of the invention may be one or more of the following. The two images provide a user with views of different perspectives of the structure. For example, the pressure sensors may provide a topographic view which identifies relatively hard regions of the structure. The imaging sensors may provide cross-sectional slices of the structure. Thus, with the slices and the topographic view, the user is able to view the structure in three dimensions, and make a more informed decision as to whether the structure is likely to be benign or malignant. It is also possible to determine the relationship between depth and hardness and to use this information to gain further knowledge of the structure. For example, the same structure may appear to have different hardnesses depending upon its depth. Knowing the depth of the structure, therefore, can correct this discrepancy.
This aspect of the invention may include one or more of the following features. The imaging sensor may comprise an ultrasound transducer, in which case the first image comprises a cross-sectional slice of the structure. The second image comprises a topographic map of the structure. The topographic map shows areas of the structure having different characteristics in different shades. An example of different characteristics includes different levels of hardness in the structure.
The pressure sensor may be part of an array of pressure sensors and the imaging sensor may be part of an array of imaging sensors. The pressure sensors may be arranged at locations along an outer perimeter of the imaging sensors. For example, the pressure sensors may be arranged to surround the imaging sensors.
A display screen displays the first and second images at a same time and an identifier that identifies the second image. A processor receives the data for the first and second images from the imaging sensor and pressure sensor, respectively, and processes the data to generate the first and second images for display on the display screen.
In general, in another aspect, the invention features obtaining image data for a structure through bodily tissue. In this aspect, a pressure sensor contacts the bodily tissue to obtain data for the structure and a position tracking device determines a location of the pressure sensor relative to the structure.
Among the advantages of this aspect of the invention may be one or more of the following. Knowing the location of the pressure sensor relative to the structure makes it possible to identify a specific region of the structure for re-examination and to control placement of the pressure sensors on the bodily tissue accordingly. Imaging sensors may also be included to obtain image data for a different image of the structure. The imaging sensors may be positioned in accordance with the location determined by the position tracking device, making re-examination more precise.
This aspect of the invention may include one or more of the following features. An imaging sensor is included that contacts the bodily tissue to obtain image data for a different image of the structure. The imaging sensor comprises an ultrasound transducer. The pressure sensor is part of an array of pressure sensors that are arranged along an outer perimeter of the imaging sensor. A display screen displays the image of the structure and an image of the apparatus relative to the structure based on the data.
The position tracking device obtains data for a body containing the structure. The display screen displays an image that is representative of the body and a location of the structure relative to the body based on the data. The position tracking device obtains the image data for the body and the location of the structure relative to the body based on fiducial points in the body.
In general, in another aspect, the invention features obtaining information relating to a structure through bodily tissue. An imaging sensor contacts the bodily tissue to obtain first information relating to the structure. A pressure sensor is oriented in a substantially same direction as the imaging sensor. The pressure sensor contacts the bodily tissue to obtain second information relating to the structure. The second information differs from the first information.
Among the advantages of this aspect of the invention may be one or more of the following. Obtaining different information about a structure facilitates identification and removal of the structure. For example, the first information may relate to a hardness of the structure and the second information may relate to a depth of the structure within the bodily tissue. This information can be used in classifying the structure as benign or malignant and, if necessary, removing the structure from the tissue.
This aspect of the invention may include one or more of the following features. The imaging sensor comprises an A-mode ultrasound transducer. A display, such as a monitor, displays the first information and the second information. A fixture guides a tissue sampling device to the structure. The fixture is movable (both vertically and horizontally) over a range of angles.
Other features and advantages will become apparent from the following description, claims, and drawings.